“Immigration shapes the destiny of the Nation,” wrote Supreme Court Justice Anthony Kennedy in his majority opinion deciding the fate of Arizona’s controversial immigration law.

Based on the court’s ruling, that destiny will continue to be shaped in Washington rather than in 50 state capitals.

Citing “the federal government’s broad, undoubted power over immigration and alien status,” the court affirmed most of a lower court’s ruling that federal immigration law trumps state law such as Arizona’s.

The state’s requirement that immigrants produce identification papers at the request of authorities was struck down. So was the imposition of criminal penalties on illegal immigrants who obtain employment (federal law imposes penalties on employers, not employees). Finally, the law authorized state law enforcement officers to arrest, without a warrant, anyone they had “probable cause” to believe was removable under immigration law.

This last provision, Kennedy wrote, “is not the system Congress created.”

The decision is encouraging not just in the details but in its broad strokes. The court’s endorsement of the Supremacy Clause and federal prerogatives is especially welcome given the myriad efforts to undermine long- established uses of federal power.

Equally welcome is the manner of the court’s decision. Instead of a 5-4 decision on habitual partisan lines, Chief Justice John Roberts joined Kennedy and the court’s liberal justices (minus Justice Elena Kagan, who recused herself) in a 5-3 decision that gave added authority to Kennedy’s solid reasoning. (We hope the court produces a similarly authoritative ruling on the health-care law.)

The court also upheld one of the four contested provisions of the Arizona law: It permitted law enforcement officers to check the immigration status of anyone they believe to be in the country illegally. Enforcing such a provision all but requires some level of racial profiling, given the preponderance of Hispanics among Arizona’s illegal alien population.

Since the state insisted that profiling wasn’t necessary, however, and the Obama administration declined to make reliance on profiling grounds for its objection to the law, the court is right to let that part of the statute play out “at this stage.”

If the provision produces clear civil-rights violations, the question of its constitutionality can be revisited.

The decision will invalidate similarly unconstitutional provisions adopted by other states (Alabama comes quickly to mind). For any still considering such measures, there are many reasons to avoid repeating Arizona’s experience. Its law was a commercial albatross and a political liability, damaging the state’s image and leading to the recall of the state senator who sponsored the legislation. Arizona spent an estimated $3 million defending the law and needlessly antagonized many of its own citizens in the process.

Altogether, the ruling is a cause for celebration. The system worked.

Editorial by Bloomberg View